Conventionally, various bleaching activators have been proposed to increase the bleaching power of oxygen-based bleaching agents such as sodium percarbonate, sodium perborate, etc. Their functions may be significantly deteriorated due to interaction with the oxygen-based bleaching agents during storage or with other components contained in a detergent. Accordingly, the bleaching activator is required to have high shelf stability. Further, the bleaching activator is required to have an excellent solubility even under conditions of washing with a weak stirring force in cold water or under conditions of bleaching by dipping.
JP-A 2001-59099 discloses bleaching activator granules excellent in solubility, wherein a bleaching activator, a nonionic surfactant having a melting point of lower than 20° C. satisfying specific dissolution conditions, and at least one nonionic surfactant selected from alkylene oxide-added nonionic surfactants having a melting point of lower than 20° C. are contained in a specific ratio.